Method of making bearing sleeves



DeC- 27, 1932- B. sTocKFLTH 1,892,172

Filed Feb. 4. 1929 Patented Dec. 27, 1932 UN1TED` STATES PATENT o FFlcE BERGER STOC'KIELETH, NILES, MICHIGAN, ASSIGNOR, BY MESNE ASSIGNHENTS, T0

THE CLEVELAND GRAPHITE BRONZE COMPANY, OF CLEVELAND, OHIO, A CORPORA- TION 0F OHIO METHOD OF MAKING BEARING SLEEVES This invention relates to improvements in methods and processes of making bearings and has special reference to renewal bearin sleeves or shells made with relatively harbacks and relatively softer linings of bearingmetal such as Babbitt metal.

his present-invention relates to improvements on my earlier invention, as disclosed in my co-pending application on methods and means for making bearing linings or sleeves, filed August 20, 1928, Serial No. 300,757, which has matured into Patent No. 1,803,513, issued May 5, 1931.

rlhe object of this present invention is to provide means and methodsk by which the quality of such composite bearing sleeves will be improved, by which the possibility of rupture between the Babbitt metal lining and the harder metal back will be eliminated, by which the necessary forming pressure may be Ilowered without lowering the quality of the product and, further, by which the surfaces both interior and exteriorwill be smoother and more accurately sized than heretofore.

In my earlier application, I have shown a method for casting Babbitt metal upon harder metal backs such as steel, bronze, or brass;

and in my co-pending application on bearing.

linings or sleeves and method of making same, filed June 5, 1928, Serial No. 283,109,1

which has matured into Patent No. 1,851,934, issued March 29, 1932, I have shown a method of accurately finishing or sizing such sleeves by the application of pressure, and this present invention has to'do particularly with improvements which facilitate and cheapen the step of accurately finishing and sizing such preformed sleeves and otherwise improving or making more certain the quality of the product, especially as to the bonding of the Babbitt metal lining tothe harder metal back.

1n this present invention, I'provide a pair of dies; that is, female and male die members,

" between which the preformed sleeve is placed and by which a very heavy forming pressure can be applied to the sleeve. Indeed, the pressure is suicient not only to form the 'Babbitt metal by causing it to flowrbut is sufficient to cause the harder metal back, such as steel, to flow likewise, resulting in a thinning of both the babbitt and the steel portions radially, but the softer metal to a eater extent, and their elongation circum erentially and sometimes longitudinally.

I have found that the forming and flowing of the two metals under the pressures employed when all of the parts are at normal atmospheric temperature often results in disrupting the bond which has been produced between the Babbitt metal and the back in the casting step, and I have found that by mainy taining the die members relatively hot, that is at a temperature approaching but not close to the melting point of the Babbitt metal,

I am enabled to gain the advantageous reheat from the die members to penetrate intol the sleeve, rendering the Babbitt lining and the tin on the outer surface of the backing easily malleable, and consequently these parts are conformed readily and relatively easily to the forming surfaces of the die members without the application of the excessive pressure which is required without the addition of this heat. Furthermore, considerably less time is required for this forming operation.

As the surface portions of the bearings are thus more readily moved and formed to conform to the die surfaces, the strain between the Babbitt metal lining and the harder metal back is greatly reduced or entirely eliminated, with the result that the bond between the Babbitt metal and the back is not ruptured but is left in its original cast condition, and in many cases-due to the heating of the dies and the heat generated by the forming operation-the bond is improved or made better.

My invention will be more readily understood by refence to the accompanying drawing forming part of this specification and in which- Fig. l is a perspective view of a bearing sleeve made by my improved method;

Fig. 2 is a cross-sectional view of the sleeve;

Fig. 3 is a fragmentary' cross-sectional view of a pair of dies and illustrating the sleeve forming operation and Fig. 4 is an end view of the sleeve, showing in dotted lines the extruded metal.

In said drawing` l indicates a finished bearing sleeve consisting of an outer semi-cylindrieal shell 2 of a relatively harder metal such as steel, bronze or brass, an inner lining 3 of relatively softer bearing metal such as Babbitt metal, the two bonded together by a thin layer or coating l of a relatively soft or malleable suitable bonding metal such as tin and the backing shell 2 covered on its outer surface by a thin coating 5 of the malleable bonding metal. It should, of course, be understood that it requires two of the sleeves, as shown, to form a complete bearing lining.

In the production of such sleeves, as described in my said co-pending applications, the backing is first formed up roughly to size and shape, preferably out of suitable sheet metal. This rough backing is then coated all over with the bonding metal such as tin by being `first dipped in a suitable cleansing bath and then into a bath of bonding metal in molten condition. The coated back is then placed in a casting machine, preferably while still hot, and the lining 3 is cast on, the heat in the back assisting in the bonding of the lining to the back through the medium of the bonding metal.

The sleeve thus roughly formed is then subjected to the final sizing and finishing step, preferably still in hot condition from the dipping and casting operations. For this final step, I provide a pair of suitably formed die members consisting of a lower die member 6 havlng a semi-cylindrical die opening 7 for producing the outer surface of the sleeve and a cooperating plunger member 8 having a semi-cylindrical lower forming end 9 for producing the inner surface of the sleeve. These die members 6 and 8 are heated by any suitable means such as a number of electric heatlng units, indicated at 10, arranged in suitable openings or holes 1l provided in the two die members.

The sleeve, prepared as described and pref- I with the utmost care, the bond between the lining and the backing may not be 100 per cent perfect; that is, there may be spots where the two are not bonded or stuck together. The process of forming, sizing and finishing the sleeves between hot dies and including the circumferential elongation and radial 'thinning of the sleeve body not only does not disrupt the bond produced in the casting step but actually improves and completes same if the cast bond is not perfect. 'Ihis elongation of the body -of the sleeve, the result of which is indicated at l2, showing the portions which are forced out of the die space, is an element in the completion of the bond between the lining and the backing7 especially under the heated conditions described. Also, the coating 5 of the bonding material on the outer surface of the backing serves to permit the pressure applied to act upon the sleeve in the forming and elongation step described, acting to a slight degree as a lubricant 'between the backing and the lower die member.

In Fig. 4 I have indicated, by showing the exuded portions 12 in dotted lines, that these portions are removed by any suitable means, such as cutting them off, after the formed sleeve is removed from the dies.

It should be understood, of course, that the die members 6 and 8 are mounted in a suitable press for operation as described.

As many modifications of the invention will readily suggest themselves to one skilled in the art, I do not limit or conne the invention to the specific details of construction and sequence of steps herein described.

I claim:

l. The herein described improvements in methods for forming a bearing liner or sleeve preformed of a harder metal back and a rela tively softer bearing metal liningthe backing having first been coated inside and out with a bonding metal such as tin, which method consists in subjecting the preformed sleeve to a relatively heavy forming pressure applied radially thereto by suitable die members and maintaining the die members heated to a point below the melting point of the lining and bonding metal, and whereby the lining, backing, and outer coating of the bonding metal are elongated circumferentially and thinned radially and caused to accurately conform to the forming surfaces of llO the die members without disrupting the bond betweenthe backing and the lining.

2. The herein described improvements in methods for forming a bearing liner or sleeve roughly preformed of a harder meta-l back and a relatively softer bearing metal lining bonded to the back by an intermediate coating of a bonding metal -such as tin, which method consists in subjecting the preformed sleeve in a relatively hot condition to a relatively heavy forming pressure between die members and maintaining the die members heated to a temperature at which the bearing metal is malleable but notV melted and the applied pressure being sufficient under the specified conditionsas to temperatures to thin the metals of the sleeve radially and to elon ate them circumferentially.

3. T e herein described improvements in` methods for forming a bearing liner or sleeve roughly preformed of a harder metal back and a rela-tively softer bearing metallining bonded to the back by an intermediate coating of a bonding metal such as tin, which has a melting point lower than that of the lining, and which method consists in subjecting the preformed sleeve in a relatively hot condition to a relatively heavy forming pressure between die members, the die members being maintained at a temperature at which both the lining and the bonding metals are malleable but not melted and the applied pressure being sufficient under the conditions to thin the metals of the sleeve radially and elongate them circumferentially. i

4. The herein described improvements in methods for forming a bearing liner or sleeve roughly preformed of a harder metal back and a relatively softer bearing metal lining bonded to the back by an intermediate coating of a bonding metal such as tin, which has a melting point lower than that of the lin.

ing, and which method consists in subjecting the preformed sleeve in a relatively hot condition to ay relatively heavy forming pressure between die members, the die members being maintained at a temperature between 200 degrees Fahrenheit and the freezing temperature of the bonding metal and the applied pressure being suilicient to thin the sleeve radially and elongate it circumferentially.

5. The herein described improvements in methods for forming a bearing liner or sleeve roughly preformed of a harder metal back and a relatively softer bearing metal lining bonded to the back by an intermediate coating of a bonding metal such as tin, which method consists in subjecting the preformed sleeve to a relativelyheavy forming pressure between die members and maintaining the die members heated approximately to the melting temperature of the bonding metal, and the applied pressure being sulicient to thin the sleeve radially and cause the substant-ial equal elongation of the metals of the sleeve in' a direction substantially parallel bonded to the back, and which method conssts in subjecting a roughly formed sleeve to pressure between suitable forming dies, the pressure being suilicient to thin the metals of the sleeve radially and substantiallyequally elongate them in a direction substantially parallel with the die surface, and maintaining the dies hot to reduce the necessary applied pressure.

7. The invention as defined in claim 6, and pre-heating the rough sleeve before applying the forming pressure.

8. The herein described method of formin a bi-metal, substantially semi-cylindrica bearing sleeve madeup of a back shell of a tough relatively hard material such as steel, and a relatively softer bearing metal lining bonded to the back by an intermediate coating of a bonding metal such as tin, and which method consists in subjecting a roughly formed sleeve in a relatively hot condition vto a relatively heavy forming pressure between relatively hot die members, the pressure applied being sutlicient under the circumstances to thin themetals of the sleeve radially and substantially equally elongate them in a di- ;ection substantially parallel with the die suraces.

9. The herein described method of forming a bearing sleeve made up of a back shell of a relatively hard metal and a lining of a relatively softer bearing metal bonded to the back. which method consists in subjecting the roughly formed sleeve to relatively heavy pressure between suitable formin dies to thin the metals of the sleeve radially and cause an elongation of the metals substantially parallel to the die surfaces.

10. The herein descrlbed method of making lined bearing shells which consists in roughly forming up a sheet metal backing, coating such backing with a suitable bonding metal such as tin, adding a lining of suitable bearing metal such as Babbitt metal which is bonded to the back through the medium of the bonding metal, then sizing, smoothing and finishing the shell by applying pressure between suitable surfaces and causing the shell to be elongated circumferentially; that is, both the backing and the lining, and permitting these parts to be extruded from the pressure surfacesvv along the longitudinal edges of the shell.

- 11. The herein described improvements 1n the pressure methodof making a lined bearing shell, which consists in causing the backing and the lining to be extruded together from the dies along the longitudinal edges of the shell.

1Q. In the pressure method of sizing and finishing bearings, the steps of preforming a back shell of relatively harder metal toapproximately the size and shape desired in the finished sleeve but slightly thicker radially, coat-ing the shell both inside and out with a suitable bonding metal, providing a lining of suitable bearing metal bonded to the back, the lining being slightly thicker radially than desired in the finished sleeve, and by means of pressure applied radially to the rough sleeve causing both the lining and the back to be elongated circumferentially While pressed between the opposed die surfaces, the adjacent surfaces of the two metals being substantially equally elongated whereby the bond between them is preserved.

13. The herein described methodof forming metal articles which consists in providing a relatively hard tough core member roughly of the shape and size desired, bonding softer' metal such as babbitt, tin or the like to the surfaces of the core member, then subjecting the article to pressure applied substantially normally to the coated surfaces and sufficient to reduce the thickness of the article and substantially equally elongate the met-als of the articles in a direction substantially parallel to the die surfaces.

1l. 'lhe herein described method of forming thin walled metal articles Which consists in providing a suitable sheet metal blank of tough metal suchV as steel, coating the surfaces of the sheet metal blank with relatively soft metal such as babbitt or tin, then subjecting the coated blank to suicient pressure applied substantially normally to the coated surfaces to reduce the thickness of the sheet metal blank and cause the substantial equal elongation of the metals of the articles in a direction substantially parallel to the die surfaces.

l5. The herein described method of mak-A ing metal articles which consists in providing a core member of suitable form and made of a relatively tough, strong metal such as steel, applying a relatively soft metal such as tin, to the surfaces of the core member and by pressure applied, by suitable die members to the article in a direction substantially normal to the'coated surfaces, compressing the coating metal upon the core member, and flowing the coatings and the core member in a direct-ion parallel Withthe die surfaces.

16. The herein described method of makingk metal articles having curved surfaces, which consists in providing a core member of a tough strong metal such as steel, and of approximately the size and shape of the finished article, preparing the surfaces of the core member by means of a bonding metal coating to bond an outerfinishing metal to the core member, applying a finishing metal 

